Content protection ticket system and method

ABSTRACT

Systems and methods for providing access to data. When an application needs to perform an action that requires access to data, the application acquires a “ticket” in order to access the data. While the application holds the ticket, it is given access to the data.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to and the benefit of commonly assignedU.S. Provisional Application having Ser. No. 60/567,158, filed on Apr.30, 2004, entitled “CONTENT PROTECTION TICKET SYSTEM AND METHOD,” whichis hereby incorporated by reference in its entirety for all purposes.

BACKGROUND

1. Technical Field

The present invention relates generally to the field of communications,and in particular to protecting content on mobile wirelesscommunications devices.

2. Description of the Related Art

Many mobile devices contain data that would be considered “sensitive,”such as the contents of e-mail messages, names and e-mail addresses ofcontacts, the times and locations of meetings, etc. As a result,existing methods may be used to protect the user's sensitive data whenthe device is in a “locked” state by storing this data in an encryptedform in the user's file system.

If the user's data is completely encrypted when the user's device islocked, applications on the device cannot have access to the data whenthe device is locked. Otherwise, if there could at any time be data inthe user's file system that is not encrypted, the device cannot be trulydeemed securely “locked”.

This effectively forces all applications on the device to stop what theyare doing when the device enters a “locked” state, since they will nolonger be able to access their data. For example, if an application isin the process of sorting a list of sensitive data, it will not be ableto continue with the sorting operation until the device is unlocked.This could increase the complexity of the application considerably,since it would have to take the “lock state” of the device intoconsideration when determining when any operation could take place andsince a device lock can be initiated at any time (e.g., by a timeout, ormanually by the user).

SUMMARY

In accordance with the teachings provided herein, systems and methodsare provided for providing access to sensitive data. As an example of asystem and method, when an application needs to perform an action thatrequires access to sensitive data, the application acquires a “ticket”in order to access the data. So long as the application holds theticket, it will be given access to sensitive data.

Another example of a method and system may include a ticket beingrequested in order to receive access to data stored on the device. Aticket is received from the device and is used to access the data storedon the device.

Another example could involve issuing a ticket to a requestor responsiveto a request to access sensitive data and to a lock status associatedwith the device. Requestors having issued tickets are tracked using aticket data store. Access is regulated to the sensitive data responsiveto possession of a ticket. Requestors can be requested to release anyissued tickets in preparation of locking the device. The device receivesnotice of release of each issued ticket and then can lock the deviceresponsive to receiving notice of release of each issued ticket, whereinthe locking disables the device from executing an application until thedevice is unlocked.

Another example could involve a content protection system having lockinginstructions executable by a device processor. The locking instructionsare configured to receive a device lock request for placing the devicein a locked state. Ticketing instructions executable by the deviceprocessor can be configured to receive a request for a ticket. Theticket can be used to access sensitive data stored on the device. Theticketing instructions are configured to provide a ticket to therequestor based upon whether the device is locked and based upon whethera device lock request for the device has been received by the lockinginstructions. The ticketing instructions are configured to hold therequest responsive to determining that the device is locked or a devicelock request has been received, and to respond to the ticket requestwhen the device is unlocked.

As will be appreciated, the disclosed systems and methods are capable ofmodifications in various respects. Accordingly, the drawings anddescription set forth below are to be regarded as illustrative in natureand not restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an overview of an example communication system in which awireless communication device may be used.

FIG. 2 is a block diagram of a further example communication systemincluding multiple networks and multiple mobile communication devices.

FIGS. 3 and 4 are block diagrams depicting the regulation of access tosensitive content.

FIG. 5 is a flowchart illustrating an operational scenario forregulating access to sensitive content stored on a device.

FIG. 6 is a flowchart illustrating an operational scenario involving arequester of sensitive content.

FIG. 7 is a block diagram of an example mobile device.

DETAILED DESCRIPTION OF THE DRAWINGS

FIG. 1 is an overview of an example communication system in which awireless communication device may be used. One skilled in the art willappreciate that there may be hundreds of different topologies, but thesystem shown in FIG. 1 helps demonstrate the operation of the encodedmessage processing systems and methods described in the presentapplication. There may also be many message senders and recipients. Thesimple system shown in FIG. 1 is for illustrative purposes only, andshows perhaps the most prevalent Internet e-mail environment wheresecurity is not generally used.

FIG. 1 shows an e-mail sender 10, the Internet 20, a message serversystem 40, a wireless gateway 85, wireless infrastructure 90, a wirelessnetwork 105 and a mobile communication device 100.

An e-mail sender system 10 may, for example, be connected to an ISP(Internet Service Provider) on which a user of the system 10 has anaccount, located within a company, possibly connected to a local areanetwork (LAN), and connected to the Internet 20, or connected to theInternet 20 through a large ASP (application service provider) such asAmerica Online (AOL). Those skilled in the art will appreciate that thesystems shown in FIG. 1 may instead be connected to a wide area network(WAN) other than the Internet, although e-mail transfers are commonlyaccomplished through Internet-connected arrangements as shown in FIG. 1.

The message server 40 may be implemented, for example, on a networkcomputer within the firewall of a corporation, a computer within an ISPor ASP system or the like, and acts as the main interface for e-mailexchange over the Internet 20. Although other messaging systems mightnot require a message server system 40, a mobile device 100 configuredfor receiving and possibly sending e-mail will normally be associatedwith an account on a message server. Perhaps the two most common messageservers are Microsoft Exchange and Lotus Domino These products are oftenused in conjunction with Internet mail routers that route and delivermail. These intermediate components are not shown in FIG. 1, as they donot directly play a role in the secure message processing describedbelow. Message servers such as server 40 typically extend beyond juste-mail sending and receiving; they also include dynamic database storageengines that have predefined database formats for data like calendars,to-do lists, task lists, e-mail and documentation.

The wireless gateway 85 and infrastructure 90 provide a link between theInternet 20 and wireless network 105. The wireless infrastructure 90determines the most likely network for locating a given user and tracksthe user as they roam between countries or networks. A message is thendelivered to the mobile device 100 via wireless transmission, typicallyat a radio frequency (RF), from a base station in the wireless network105 to the mobile device 100. The particular network 105 may bevirtually any wireless network over which messages may be exchanged witha mobile communication device.

As shown in FIG. 1, a composed e-mail message 15 is sent by the e-mailsender 10, located somewhere on the Internet 20. This message 15 isnormally fully in the clear and uses traditional Simple Mail TransferProtocol (SMTP), RFC822 headers and Multipurpose Internet Mail Extension(MIME) body parts to define the format of the mail message. Thesetechniques are all well known to those skilled in the art. The message15 arrives at the message server 40 and is normally stored in a messagestore. Most known messaging systems support a so-called “pull” messageaccess scheme, wherein the mobile device 100 must request that storedmessages be forwarded by the message server to the mobile device 100.Some systems provide for automatic routing of such messages which areaddressed using a specific e-mail address associated with the mobiledevice 100. In a preferred embodiment described in further detail below,messages addressed to a message server account associated with a hostsystem such as a home computer or office computer which belongs to theuser of a mobile device 100 are redirected from the message server 40 tothe mobile device 100 as they are received.

Regardless of the specific mechanism controlling the forwarding ofmessages to the mobile device 100, the message 15, or possibly atranslated or reformatted version thereof, is sent to the wirelessgateway 85. The wireless infrastructure 90 includes a series ofconnections to wireless network 105. These connections could beIntegrated Services Digital Network (ISDN), Frame Relay or Ticonnections using the TCP/IP protocol used throughout the Internet. Asused herein, the term “wireless network” is intended to include threedifferent types of networks, those being (1) data-centric wirelessnetworks, (2) voice-centric wireless networks and (3) dual-mode networksthat can support both voice and data communications over the samephysical base stations. Combined dual-mode networks include, but are notlimited to, (1) Code Division Multiple Access (CDMA) networks, (2) theGroupe Special Mobile or the Global System for Mobile Communications(GSM) and the General Packet Radio Service (GPRS) networks, and (3)future third-generation (3G) networks like Enhanced Data-rates forGlobal Evolution (EDGE) and Universal Mobile Telecommunications Systems(UMTS). Some older examples of data-centric network include the Mobitex™Radio Network and the DataTAC™ Radio Network. Examples of oldervoice-centric data networks include Personal Communication Systems (PCS)networks like GSM, and TDMA systems.

FIG. 2 is a block diagram of a further example communication systemincluding multiple networks and multiple mobile communication devices.The system of FIG. 2 is substantially similar to the FIG. 1 system, butincludes a host system 30, a redirection program 45, a mobile devicecradle 65, a wireless virtual private network (VPN) router 75, anadditional wireless network 110 and multiple mobile communicationdevices 100. As described above in conjunction with FIG. 1, FIG. 2represents an overview of a sample network topology. Although theencoded message processing systems and methods described herein may beapplied to networks having many different topologies, the network ofFIG. 2 is useful in understanding an automatic e-mail redirection systemmentioned briefly above.

The central host system 30 will typically be a corporate office or otherLAN, but may instead be a home office computer or some other privatesystem where mail messages are being exchanged. Within the host system30 is the message server 40, running on some computer within thefirewall of the host system, that acts as the main interface for thehost system to exchange e-mail with the Internet 20. In the system ofFIG. 2, the redirection program 45 enables redirection of data itemsfrom the server 40 to a mobile communication device 100. Although theredirection program 45 is shown to reside on the same machine as themessage server 40 for ease of presentation, there is no requirement thatit must reside on the message server. The redirection program 45 and themessage server 40 are designed to co-operate and interact to allow thepushing of information to mobile devices 100. In this installation, theredirection program 45 takes confidential and non-confidential corporateinformation for a specific user and redirects it out through thecorporate firewall to mobile devices 100. A more detailed description ofthe redirection software 45 may be found in the commonly assigned U.S.Pat. No. 6,219,694 (“the '694 patent”), entitled “System and Method forPushing Information From A Host System To A Mobile Data CommunicationDevice Having A Shared Electronic Address”, and issued to the assigneeof the instant application on Apr. 17, 2001, which is herebyincorporated into the present application by reference. This pushtechnique may use a wireless friendly encoding, compression andencryption technique to deliver all information to a mobile device, thuseffectively extending the security firewall to include each mobiledevice 100 associated with the host system 30.

As shown in FIG. 2, there may be many alternative paths for gettinginformation to the mobile device 100. One method for loading informationonto the mobile device 100 is through a port designated 50, using adevice cradle 65. This method tends to be useful for bulk informationupdates often performed at initialization of a mobile device 100 withthe host system 30 or a computer 35 within the system 30. The other mainmethod for data exchange is over-the-air using wireless networks todeliver the information. As shown in FIG. 2, this may be accomplishedthrough a wireless VPN router 75 or through a traditional Internetconnection 95 to a wireless gateway 85 and a wireless infrastructure 90,as described above. The concept of a wireless VPN router 75 is new inthe wireless industry and implies that a VPN connection could beestablished directly through a specific wireless network 110 to a mobiledevice 100. The possibility of using a wireless VPN router 75 has onlyrecently been available and could be used when the new Internet Protocol(IP) Version 6 (IPV6) arrives into IP-based wireless networks. This newprotocol will provide enough IP addresses to dedicate an IP address toevery mobile device 100 and thus make it possible to push information toa mobile device 100 at any time. A principal advantage of using thiswireless VPN router 75 is that it could be an off-the-shelf VPNcomponent, thus it would not require a separate wireless gateway 85 andwireless infrastructure 90 to be used. A VPN connection would preferablybe a Transmission Control Protocol (TCP)/IP or User Datagram Protocol(UDP)/IP connection to deliver the messages directly to the mobiledevice 100. If a wireless VPN 75 is not available then a link 95 to theInternet 20 is the most common connection mechanism available and hasbeen described above.

In the automatic redirection system of FIG. 2, a composed e-mail message15 leaving the e-mail sender 10 arrives at the message server 40 and isredirected by the redirection program 45 to the mobile device 100. Asthis redirection takes place the message 15 is re-enveloped, asindicated at 80, and a possibly proprietary compression and encryptionalgorithm can then be applied to the original message 15. In this way,messages being read on the mobile device 100 are no less secure than ifthey were read on a desktop workstation such as 35 within the firewall.All messages exchanged between the redirection program 45 and the mobiledevice 100 preferably use this message repackaging technique. Anothergoal of this outer envelope is to maintain the addressing information ofthe original message except the sender's and the receiver's address.This allows reply messages to reach the appropriate destination, andalso allows the “from” field to reflect the mobile user's desktopaddress. Using the user's e-mail address from the mobile device 100allows the received message to appear as though the message originatedfrom the user's desktop system 35 rather than the mobile device 100.

With reference back to the port 50 and cradle 65 connectivity to themobile device 100, this connection path offers many advantages forenabling one-time data exchange of large items. For those skilled in theart of personal digital assistants (PDAs) and synchronization, the mostcommon data exchanged over this link is Personal Information Management(PIM) data 55. When exchanged for the first time this data tends to belarge in quantity, bulky in nature and requires a large bandwidth to getloaded onto the mobile device 100 where it can be used on the road. Thisserial link may also be used for other purposes, including setting up aprivate security key 111 such as an S/MIME or PGP specific private key,the Certificate (Cert) of the user and their Certificate RevocationLists (CRLs) 60. The private key is preferably exchanged so that thedesktop 35 and mobile device 100 share one personality and one methodfor accessing all mail. The Cert and CRLs are normally exchanged oversuch a link because they represent a large amount of the data that isrequired by the device for S/MIME, PGP and other public key securitymethods.

FIG. 3 illustrates an approach for regulating access to sensitive data.When an application 200 needs to perform an action that requires accessto sensitive data 205, the application 200 requires a “ticket” 210(e.g., token, etc.) to guarantee it access to the data 205. Theapplication 200 requests ticket 210 from the mobile device, such asthrough the device's operating system 215. If the device 100 is in anunlocked state, the operating system 215 will return a ticket 210 to theapplication 200. If the device is in a locked state, the operatingsystem 215 will block the application 200 from running further until thedevice is unlocked, at which point it will return a ticket 210 to theapplication 200 and allow it to continue running.

So long as the application 200 holds the ticket 210, it will be givenaccess to sensitive data 205. Even if the user requests that the devicebe locked, the application 200 will continue to have access to the data205 until it releases its ticket 210. After the ticket 210 has beenreleased, however, the data 205 will be inaccessible, as though thedevice is in a locked state. For example, if an application 200 needs tosort its data, it can request a ticket 210 from the operating system215, and once it has the ticket 210, the application 200 can be assuredthat it will be able to complete the sorting operation, at which pointit can release the ticket 210. Subsequent sorting operations will beblocked at the point at which the application 200 requests a ticket 210,until the device is next unlocked.

Accordingly, the system depicted in the example of FIG. 3 allowsapplications 200 to complete the actions they are in the process ofperforming, and to allow them to notify the operating system 215 thatthey have finished their actions so that the operating system 215 canreliably say that the user's device is “locked”. When an indication hasbeen given that the device is to be in a locked state, the applications200 are requested to release their tickets 210. An application 200 cancontinue to hold the ticket 210 until after it has completed itsaccessing of sensitive data (e.g., completed performing a decryptionoperation involving the sensitive data).

As shown in FIG. 4, the operating system 250 can keep track through aticket data store 255 of which applications 260 have tickets 265 andwill not consider the device to be truly locked until all of theapplications 260 on the device have released tickets 265. Once they haveall been released, the operating system 250 can reliably say that noapplication 260 on the device has access to sensitive data 270, and cantherefore indicate to the user that the device is securely locked.

Applications 260 are free to acquire tickets at any time. However, asystem may be configured such that applications 260 acquire tickets uponreceiving notification that the device is to enter into a locked state.

The systems and methods disclosed herein are presented only by way ofexample and are not meant to limit the scope of the invention. Othervariations of the systems and methods described above will be apparentto those skilled in the art and as such are considered to be within thescope of the invention. For example, the systems and methods describedherein may be used with many different operational scenarios, such asthe operational scenario depicted in FIG. 5.

FIG. 5 depicts an operational scenario which begins at step 280. At step282, a request is received from a requester. The request indicates thatthe requestor would like to access sensitive content. As describedabove, sensitive content can be the contents of e-mail messages, namesand e-mail addresses of contacts, the times and locations of meetings,among many others. The requester can be an application residing on thedevice, such as, for example, an e-mail application requesting access toan e-mail message.

In step 284, a ticket is issued to the requestor in response to therequest to access sensitive content. The ticket enables the requestor toobtain access to sensitive content stored in a device data store. Theticket can be issued by the device processor when the device is in anunlocked state. However, when the device is locked, the device processorcan hold the ticket request until the device is unlocked.

As shown in step 286, the device uses the ticket to regulate access tothe sensitive content. In this operational scenario, access to thesensitive content is regulated by controlling access to the sensitivecontent on the data store. A device processor then may requirepossession of the ticket prior to enabling access to the sensitivecontent for the requestor.

A requestor can acquire a ticket in accordance with the operationalscenario shown in FIG. 6. The operational scenario begins at step 290.At step 292, a requestor requests a ticket for accessing sensitivecontent. As described above, the requester may be an application, suchas, for example, an e-mail application requesting access to a messagestored on the data store. It should be noted that the request for aticket could be implicit within a request for access to sensitiveinformation.

In step 294, the requester receives a ticket. The ticket is configuredto enable the requestor with the ability to access sensitive contentstored on the device. As shown in step 296, the requestor is configuredto use the ticket to obtain access to the sensitive content. Forexample, when access to sensitive content is desired, the requesterwould provide the ticket to a device processor, the device processorwould examine the ticket, and determine whether the requestor possesseda valid ticket for accessing sensitive information from the data store.For example, sensitive information could be encrypted, such that thedevice processor provides access to the sensitive content upondetermining that the requestor possesses a valid ticket. The operationalscenario ends at step 298. It should be understood that steps and theorder of the steps in the processing of this operational scenarios (andof the other processing flows described herein) may be altered, modifiedand/or augmented and still achieve the desired outcome.

As another example of the wide scope of the systems and methodsdisclosed herein, the systems and methods may be used with manydifferent computers and devices, such as a wireless mobilecommunications device shown in FIG. 7. With reference to FIG. 7, themobile device 100 is a dual-mode mobile device and includes atransceiver 311, a microprocessor 338, a display 322, non-volatilememory 324, random access memory (RAM) 326, one or more auxiliaryinput/output (I/O) devices 328, a serial port 330, a keyboard 332, aspeaker 334, a microphone 336, a short-range wireless communicationssub-system 340, and other device sub-systems 342.

The transceiver 311 includes a receiver 312, a transmitter 314, antennas316 and 318, one or more local oscillators 313, and a digital signalprocessor (DSP) 320. The antennas 316 and 318 may be antenna elements ofa multiple-element antenna, and are preferably embedded antennas.However, the systems and methods described herein are in no wayrestricted to a particular type of antenna, or even to wirelesscommunication devices.

The mobile device 100 is preferably a two-way communication devicehaving voice and data communication capabilities. Thus, for example, themobile device 100 may communicate over a voice network, such as any ofthe analog or digital cellular networks, and may also communicate over adata network. The voice and data networks are depicted in FIG. 7 by thecommunication tower 319. These voice and data networks may be separatecommunication networks using separate infrastructure, such as basestations, network controllers, etc., or they may be integrated into asingle wireless network.

The transceiver 311 is used to communicate with the network 319, andincludes the receiver 312, the transmitter 314, the one or more localoscillators 313 and the DSP 320. The DSP 320 is used to send and receivesignals to and from the transceivers 316 and 318, and also providescontrol information to the receiver 312 and the transmitter 314. If thevoice and data communications occur at a single frequency, orclosely-spaced sets of frequencies, then a single local oscillator 313may be used in conjunction with the receiver 312 and the transmitter314. Alternatively, if different frequencies are utilized for voicecommunications versus data communications for example, then a pluralityof local oscillators 313 can be used to generate a plurality offrequencies corresponding to the voice and data networks 319.Information, which includes both voice and data information, iscommunicated to and from the transceiver 311 via a link between the DSP320 and the microprocessor 338.

The detailed design of the transceiver 311, such as frequency band,component selection, power level, etc., will be dependent upon thecommunication network 319 in which the mobile device 100 is intended tooperate. For example, a mobile device 100 intended to operate in a NorthAmerican market may include a transceiver 311 designed to operate withany of a variety of voice communication networks, such as the Mobitex orDataTAC mobile data communication networks, AMPS, TDMA, CDMA, PCS, etc.,whereas a mobile device 100 intended for use in Europe may be configuredto operate with the GPRS data communication network and the GSM voicecommunication network. Other types of data and voice networks, bothseparate and integrated, may also be utilized with a mobile device 100.

Depending upon the type of network or networks 319, the accessrequirements for the mobile device 100 may also vary. For example, inthe Mobitex and DataTAC data networks, mobile devices are registered onthe network using a unique identification number associated with eachmobile device. In GPRS data networks, however, network access isassociated with a subscriber or user of a mobile device. A GPRS devicetypically requires a subscriber identity module (“SIM”), which isrequired in order to operate a mobile device on a GPRS network. Local ornon-network communication functions (if any) may be operable, withoutthe SIM device, but a mobile device will be unable to carry out anyfunctions involving communications over the data network 319, other thanany legally required operations, such as ‘911’ emergency calling.

After any required network registration or activation procedures havebeen completed, the mobile device 100 may the send and receivecommunication signals, including both voice and data signals, over thenetworks 319. Signals received by the antenna 316 from the communicationnetwork 319 are routed to the receiver 312, which provides for signalamplification, frequency down conversion, filtering, channel selection,etc., and may also provide analog to digital conversion. Analog todigital conversion of the received signal allows more complexcommunication functions, such as digital demodulation and decoding to beperformed using the DSP 320. In a similar manner, signals to betransmitted to the network 319 are processed, including modulation andencoding, for example, by the DSP 320 and are then provided to thetransmitter 314 for digital to analog conversion, frequency upconversion, filtering, amplification and transmission to thecommunication network 319 via the antenna 318.

In addition to processing the communication signals, the DSP 320 alsoprovides for transceiver control. For example, the gain levels appliedto communication signals in the receiver 312 and the transmitter 314 maybe adaptively controlled through automatic gain control algorithmsimplemented in the DSP 320. Other transceiver control algorithms couldalso be implemented in the DSP 320 in order to provide moresophisticated control of the transceiver 311.

The microprocessor 338 preferably manages and controls the overalloperation of the mobile device 100. Many types of microprocessors ormicrocontrollers could be used here, or, alternatively, a single DSP 320could be used to carry out the functions of the microprocessor 338.Low-level communication functions, including at least data and voicecommunications, are performed through the DSP 320 in the transceiver311. Other, high-level communication applications, such as a voicecommunication application 324A, and a data communication application324B may be stored in the non-volatile memory 324 for execution by themicroprocessor 338. For example, the voice communication module 324A mayprovide a high-level user interface operable to transmit and receivevoice calls between the mobile device 100 and a plurality of other voiceor dual-mode devices via the network 319. Similarly, the datacommunication module 324B may provide a high-level user interfaceoperable for sending and receiving data, such as e-mail messages, files,organizer information, short text messages, etc., between the mobiledevice 100 and a plurality of other data devices via the networks 319.

The microprocessor 338 also interacts with other device subsystems, suchas the display 322, the RAM 326, the auxiliary input/output (I/O)subsystems 328, the serial port 330, the keyboard 332, the speaker 334,the microphone 336, the short-range communications subsystem 340 and anyother device subsystems generally designated as 342.

Some of the subsystems shown in FIG. 7 perform communication-relatedfunctions, whereas other subsystems may provide “resident” or on-devicefunctions. Notably, some subsystems, such as the keyboard 332 and thedisplay 322 may be used for both communication-related functions, suchas entering a text message for transmission over a data communicationnetwork, and device-resident functions such as a calculator or task listor other PDA type functions.

Operating system software used by the microprocessor 338 is preferablystored in a persistent store such as non-volatile memory 324. Thenon-volatile memory 324 may be implemented, for example, as a Flashmemory component, or as battery backed-up RAM. In addition to theoperating system, which controls low-level functions of the mobiledevice 310, the non-volatile memory 324 includes a plurality of softwaremodules 324A-324N that can be executed by the microprocessor 338 (and/orthe DSP 320), including a voice communication module 324A, a datacommunication module 324B, and a plurality of other operational modules324N for carrying out a plurality of other functions. These modules areexecuted by the microprocessor 338 and provide a high-level interfacebetween a user and the mobile device 100. This interface typicallyincludes a graphical component provided through the display 322, and aninput/output component provided through the auxiliary I/O 328, keyboard332, speaker 334, and microphone 336. The operating system, specificdevice applications or modules, or parts thereof, may be temporarilyloaded into a volatile store, such as RAM 326 for faster operation.Moreover, received communication signals may also be temporarily storedto RAM 326, before permanently writing them to a file system located ina persistent store such as the Flash memory 324.

An exemplary application module 324N that may be loaded onto the mobiledevice 100 is a personal information manager (PIM) application providingPDA functionality, such as calendar events, appointments, and taskitems. This module 324N may also interact with the voice communicationmodule 324A for managing phone calls, voice mails, etc., and may alsointeract with the data communication module for managing e-mailcommunications and other data transmissions. Alternatively, all of thefunctionality of the voice communication module 324A and the datacommunication module 324B may be integrated into the PIM module.

The non-volatile memory 324 preferably also provides a file system tofacilitate storage of PIM data items on the device. The PIM applicationpreferably includes the ability to send and receive data items, eitherby itself, or in conjunction with the voice and data communicationmodules 324A, 324B, via the wireless networks 319. The PIM data itemsare preferably seamlessly integrated, synchronized and updated, via thewireless networks 319, with a corresponding set of data items stored orassociated with a host computer system, thereby creating a mirroredsystem for data items associated with a particular user.

Context objects representing at least partially decoded data items, aswell as fully decoded data items, are preferably stored on the mobiledevice 100 in a volatile and non-persistent store such as the RAM 326.Such information may instead be stored in the non-volatile memory 324,for example, when storage intervals are relatively short, such that theinformation is removed from memory soon after it is stored. However,storage of this information in the RAM 326 or another volatile andnon-persistent store is preferred, in order to ensure that theinformation is erased from memory when the mobile device 100 losespower. This prevents an unauthorized party from obtaining any storeddecoded or partially decoded information by removing a memory chip fromthe mobile device 100, for example.

The mobile device 100 may be manually synchronized with a host system byplacing the device 100 in an interface cradle, which couples the serialport 330 of the mobile device 100 to the serial port of a computersystem or device. The serial port 330 may also be used to enable a userto set preferences through an external device or software application,or to download other application modules 324N for installation. Thiswired download path may be used to load an encryption key onto thedevice, which is a more secure method than exchanging encryptioninformation via the wireless network 319. Interfaces for other wireddownload paths may be provided in the mobile device 100, in addition toor instead of the serial port 330. For example, a USB port would providean interface to a similarly equipped personal computer.

Additional application modules 324N may be loaded onto the mobile device100 through the networks 319, through an auxiliary I/O subsystem 328,through the serial port 330, through the short-range communicationssubsystem 340, or through any other suitable subsystem 342, andinstalled by a user in the non-volatile memory 324 or RAM 326. Suchflexibility in application installation increases the functionality ofthe mobile device 100 and may provide enhanced on-device functions,communication-related functions, or both. For example, securecommunication applications may enable electronic commerce functions andother such financial transactions to be performed using the mobiledevice 100.

When the mobile device 100 is operating in a data communication mode, areceived signal, such as a text message or a web page download, isprocessed by the transceiver module 311 and provided to themicroprocessor 338, which preferably further processes the receivedsignal in multiple stages as described above, for eventual output to thedisplay 322, or, alternatively, to an auxiliary I/O device 328. A userof mobile device 100 may also compose data items, such as e-mailmessages, using the keyboard 332, which is preferably a completealphanumeric keyboard laid out in the QWERTY style, although otherstyles of complete alphanumeric keyboards such as the known DVORAK stylemay also be used. User input to the mobile device 100 is furtherenhanced with a plurality of auxiliary I/O devices 328, which mayinclude a thumbwheel input device, a touchpad, a variety of switches, arocker input switch, etc. The composed data items input by the user maythen be transmitted over the communication networks 319 via thetransceiver module 311.

When the mobile device 100 is operating in a voice communication mode,the overall operation of the mobile device is substantially similar tothe data mode, except that received signals are preferably be output tothe speaker 334 and voice signals for transmission are generated by amicrophone 336. Alternative voice or audio I/O subsystems, such as avoice message recording subsystem, may also be implemented on the mobiledevice 100. Although voice or audio signal output is preferablyaccomplished primarily through the speaker 334, the display 322 may alsobe used to provide an indication of the identity of a calling party, theduration of a voice call, or other voice call related information. Forexample, the microprocessor 338, in conjunction with the voicecommunication module and the operating system software, may detect thecaller identification information of an incoming voice call and displayit on the display 322.

A short-range communications subsystem 340 is also included in themobile device 100. The subsystem 340 may include an infrared device andassociated circuits and components, or a short-range RF communicationmodule such as a Bluetooth™ module or an 802.11 module, for example, toprovide for communication with similarly-enabled systems and devices.Those skilled in the art will appreciate that “Bluetooth” and “802.11”refer to sets of specifications, available from the Institute ofElectrical and Electronics Engineers, relating to wireless personal areanetworks and wireless local area networks, respectively.

The systems' and methods' data may be stored in one or more data stores.The data stores can be of many different types of storage devices andprogramming constructs, such as RAM, ROM, Flash memory, programming datastructures, programming variables, etc. It is noted that data structuresdescribe formats for use in organizing and storing data in databases,programs, memory, or other computer-readable media for use by a computerprogram.

The systems and methods may be provided on many different types ofcomputer-readable media including computer storage mechanisms (e.g.,CD-ROM, diskette, RAM, flash memory, computer's hard drive, etc.) thatcontain instructions for use in execution by a processor to perform themethods' operations and implement the systems described herein.

The computer components, software modules, functions and data structuresdescribed herein may be connected directly or indirectly to each otherin order to allow the flow of data needed for their operations. It isalso noted that a module or processor includes but is not limited to aunit of code that performs a software operation, and can be implementedfor example as a subroutine unit of code, or as a software function unitof code, or as an object (as in an object-oriented paradigm), or as anapplet, or in a computer script language, or as another type of computercode.

1. A method of regulating access to sensitive data on a device,comprising the steps of: requesting a ticket to obtain access to datastored on the device; receiving a ticket from the device; and using thereceived ticket to access data stored on the device.
 2. The method ofclaim 1, wherein the data is sensitive data which is stored on thedevice.
 3. The method of claim 2, wherein the sensitive data is at leastdata selected from the group containing e-mail message content, contactnames and e-mail addresses, or times and locations of meetings.
 4. Themethod of claim 1, wherein the data comprises encrypted data.
 5. Themethod of claim 4, further comprising the step of decrypting theencrypted data responsive to receiving the ticket.
 6. The method ofclaim 5, further comprising the step of receiving a request to releasethe ticket.
 7. The method of claim 6, further comprising the step ofreleasing the ticket, thereby allowing the device to enter a lockedstate.
 8. The method of claim 7, wherein the encrypted content is nolonger accessible by a requestor after the ticket has been released. 9.The method of claim 1, wherein the requester is an application executingon the device.
 10. The method of claim 9, further comprising the step ofreceiving a denial of the ticket request when the device is in a lockedstate.
 11. The method of claim 10, further comprising the step ofblocking the application from executing while the device is in thelocked state.
 12. The method of claim 11, further comprising the step ofcontinuing the execution of the application when the device is unlocked.13. The method of claim 1, further comprising receiving notificationthat the device processor is entering a locked state prior to requestinga ticket from the device processor.
 14. The method of claim 1, furthercomprising the step of allowing applications to complete the actionsthey are in the process of performing, and allowing them to notify thedevice's operating system that they have finished their actions so thatthe device can enter a locked state.
 15. The method of claim 1, whereinthe device is a wireless mobile communication device.
 16. Computersoftware stored on one or more computer readable media, the computersoftware comprising program code for carrying out a method according toclaim
 1. 17. A method of regulating access to sensitive data on awireless mobile communication device, the method comprising the stepsof: receiving a request from a requester, wherein the request isdirected to accessing sensitive data stored on the wireless mobilecommunication device; issuing a ticket to the requestor responsive tothe request to access sensitive data and a lock status associated withthe wireless mobile communication device; tracking requestors havingissued tickets using a ticket data store; regulating access to thesensitive data responsive to possession of a ticket; requesting thatrequesters release any issued tickets in preparation of locking thedevice; receiving notice of release of each issued ticket; and lockingthe device responsive to receiving notice of release of each issuedticket, such that the device is disabled from executing an applicationuntil the device is unlocked.
 18. The method of claim 17, furthercomprising the steps of: unlocking the device; and responding to ticketrequests after the device is unlocked.
 19. A content protection systemconfigured to regulate access to sensitive content stored on a wirelessmobile communication device, the system comprising: locking instructionsexecutable by a device processor; wherein the locking instructions areconfigured to receive a device lock request for placing the device in alocked state; and ticketing instructions executable by the deviceprocessor; wherein the ticketing instructions are configured to receivea request for a ticket; wherein the ticket is used to access sensitivedata stored on the device; wherein the ticketing instructions areconfigured to provide a ticket to the requester based upon whether thedevice is locked and based upon whether a device lock request for thedevice has been received by the locking instructions; wherein theticketing instructions are configured to hold the request responsive todetermining that the device is locked or a device lock request has beenreceived, and respond to the ticket request when the device is unlocked.20. The content protection system of claim 19 further comprising: aticket data store to track any requesters that have tickets.
 21. Thecontent protection system of claim 20, wherein the ticketinginstructions are further configured to request the release of issuedtickets responsive to the locking instructions receiving a device lockrequest.